The term Compact Secondary Substation (CSS) is typically used for trans-former stations in which the power from the main electricity net is transformed from medium voltage (MV), which is in the range 1-50 kV, to low voltage (LV), which is in the range of <1000 Volts. Typical CSS are produced with a concrete foundation and a concrete or metal housing on top of the foundation. Examples of typical prior art CSSs are shown in FIG. 1a and FIG. 1b. 
A prior art CSS is typically delivered as a complete building with a foundation plate on which the transformer, the MV electrics and the LV electrics are mounted already and covered by a housing. This entirely equipped building, when delivered, has to be connected to the MV cables and LV—typically coming up from the ground—which are inserted into the housing through trench like openings in both end of the housing. As the cables are stiff and difficult to handle, the connection to the electricity net is a tedious task. In addition, also the production of the various parts forming the final layout of the station is not fully optimized.
It would be desirable to ease the installation phase, and in particular the connection to the electricity net when the transformer is delivered. In addition, it would be also desirable to provide a solution which, while improving the installation phase, will also allow easing the production phase of the various components forming the layout of the station.